Project Summary/Abstract Radiofrequency ablation (RFA) is a minimally invasive method used to treat solid tumors, commonly primary liver cancers and metastases, which are accessible percutaneously via a sharp needle. Imaging guidance, typically by ultrasound or CT, is required for probe placement, but these methods are incapable of monitoring the progress of the procedure. Additional imaging sessions are required to initially locate the tumor and to assess the effectiveness of the therapy. The overall goal of this project is to translate into clinical practice a novel MRI-mediated RFA therapy. In this method, RF energy is provided and controlled by the MRI scanner, eliminating the need for an external RF generator and a grounding pad. The MRI scanner additionally offers superior soft tissue contrast for tumor localization and real time guidance of RF probe placement using a commercial gradient-based navigation system. Additionally, monitoring of tissue (rather than probe) temperature is possible during the procedure, permitting immediate assessment of the success of the ablation. Eliminating the grounding pad reduces the possibility of patient burns, and therefore increases patient safety. An initial R21 exploratory grant funded basic discovery research into this technology, comprising theoretic, scientific and technical development of MRI-mediated RFA, resulting in the demonstration of proof of principle in phantoms, tissue specimens, animal cadavers and live animals. The purpose of the current project is to translate these basic findings into a safe and practical system for clinical use, and to conduct a human clinical pilot project to assess if a full clinical trial is warranted. Specific aims include: 1- Develop integrated biopsy and RFA probes for MRI-mediated RF ablation. 2 - Optimize the performance of MRI-mediated RFA in phantom study. 3 - Optimize performance and safety of MRI-mediated biopsy and RFA in an animal study. 4 - Conduct the required regulatory activities needed to enable human study of the system. 5 - Perform pilot study in humans with liver cancer to be treated by chemotherapy. The long term goal of the research is to develop a time-efficient, cost-effective, minimally invasive ?one-stop shop? treatment for solid tumors treatable by thermal ablation. If successful, it will provide a powerful diagnostic and therapeutic tool that can be used on any MRI scanner with low cost disposable devices and without the need to add major external apparatus. This is expected to facilitate the use of MRI-guided RFA to treat a wide range of tumors as a replacement for more invasive and more costly surgical management, contributing to the PHS mission of improving health care delivery while reducing cost and patient discomfort.